Tag: Daylighting

The Importance of Right Lighting

In the last couple of years “everybody” has learned about the great cost savings to be achieved by switching to LED lights, direct cost savings of over 50% with additional savings due to reducing load on AC and reducing O&M. LEDs can be used in so many situations, can be dimmed, and now fit in virtually every type of fixture or ballast.

Thus the temptation is just to go to the store and pick up a bunch of LEDs and begin to substitute. Sure you’ll save some cost. But that’s a big mistake and you can actually harm the productivity of your workers, the ability to do business by your tenants, and the sellability of product by the retailers in your buildings.

In fact, even if you are not changing to LEDs, it is important to review your building’s lighting, as the very way we work has changed, as we have gone from reading and writing on paper exclusively to the common use of computers and other screens. Screens supply some light. Thus overhead lighting needs (number of lumens) of office workers to function well have dropped somewhat. Over-lighting is a potential issue, which increases costs, and may adversely affect worker health, mood, and productivity.


In the “old” days of exclusive working with paper, the recommended lighting levels were as high as 1,000 luxs (1 lux = 1 lumen/sq. meter). However, the US General Services Administration now recommends levels such as 500 lux for open offices, 300 lux for conference rooms, and less in other areas.

Therefore, it is useful before and after changing a building’s lighting to perform a lighting study. Have light readings taken to determine whether you are over-lighting an area. It may be tempting to say after an LED upgrade “I don’t care if I over-light my areas. My electricity costs are now so low, I don’t mind over-lighting.” This is a mistake as over-lighting stresses employees, causes headaches and anxiety, and may interfere with sleep and circadian rhythms. In other words, it may affect productivity, which could cost your company more money than is saved by switching to LEDs.

If you find areas of over-lighting, do some de-lamping: remove some lamps to bring the light levels down to the recommended intensities. Not only will you improve the productivity of your workers and tenants, but you will save additional energy costs and O&M having fewer lights using electricity. But make sure you don’t overdo de-lamping.

Finally, take into consideration the time of day. During different times of day, sunlight may enter certain workspaces. During those times, allow the sunlight in. Workers work better under natural light. Either procure/use daylighting sensors to adjust the artificial light to the sunlight entering from outside or turn down or off certain banks of lights when the sun shines in. Again, make the effort not to over-light areas.

EE Reports has the expertise to conduct lighting studies for you and to make determinations of what types and intensities of lights should be brought in to meet standards for different uses and security. We can recommend the right daylight sensors for different parts of your building and where to re-locate lighting to get not the most, but the best lighting for your tenants and workers, based on their job needs. Contact Marc Karell, VP Engineerng,  today at 914-584-6720 or marc@eereports.com

Let There Be Daylight by Green Light NY

Let There Be Daylight is Green Light New York’s first research report. It evolved into the Living Lab proof of concept project..

This report advocates for advanced daylighting systems to become a standard feature of New York City office spaces. It follows a careful analysis of the technical, practical, and energy savings potential that advanced daylighting systems can provide to NYC buildings.

New York City has the largest market for office space in the country. These offices are condensed into a proportionately small number of buildings and are managed and owned by a smaller number of people than in other urban office markets, making a transition to advanced daylighting systems more easily attainable. Furthermore, many of the City’s older non-residential buildings are already designed to capitalize on the benefits of daylight, as they were built when electric lights were just beginning to be implemented. The onset of more stringent energy codes requires an increased number of lighting retrofits in existing buildings. Let There Be Daylight explores these unique conditions in NYC that present opportunity to drive substantial demand for advanced daylighting systems.


Our analysis finds that 114 million square feet of New York City office space can easily accommodate comprehensive daylighting control retrofits to achieve electric peak demand reduction equivalent to 160 megawatts, as well as 340 gigawatt hours of electricity savings. Deployment of daylighting systems is an opportunity for New York City building owners and tenants to benefit from $70 million in energy cost savings each year.

“Peak demand” is the time during the day when the most energy is being used. It is also when energy costs the most to produce. Coincidentally, peak demand hours coincide with the times of day when sunlight is most readily available. Therefore, daylighting systems not only have the potential to save energy, but to also cut back on the dirtiest, least efficient energy being produced.


Let There Be Daylight explores the potential of advanced daylighting systems for New York City and the barriers and strategies for implementation. The report is a collaborative work of Yetsuh Frank and Richard Yancey of Green Light New York and Adam Hinge of Sustainable Energy Partnerships published in 2012.

Click HERE for the full report

As of 2014, Green Light New York is now known as the Building Energy Exchange.

via Building Energy Exchange.